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Ice Maker Making Ice Slow

I have Hoshizaki KM-500MAH air cooled unit and it is producing ice but at a slow pace. I emptied the machine 2 days ago to clean it and it only has the bin half full. The machine was cleaned recently with lime away and is very clean. The ice that is made comes out perfect. The air filter on the unit was missing when I inspected it and tons of dust and such were built up all over inside the unit and on the condenser coils/aluminum "fins". I tried to blow out the dust, vacuum it out and use a small, fine brush (that did no damage the aluminum "fins") and was able to get out a lot of the build up but most of it is seriously stuck in there. I am going to assume the bad air flow is to blame for the slow ice making. Either way, I know this is an issue because not a lot of air is flowing through the coils. A minimal amount of air seems to be actually passing through. My question is, what can I use to clean the aluminum "fins" and condenser coils? The build up appears to be dust, dirt and grease from a restaurant. I was told car brake cleaner is a non-rinse cleaner that would work but am skeptical. Thanks in advance!

Reduced condenser airflow will definitely cause slow ice making. If there are other issues, they will be hard to see without proper airflow as fell. You need to correct the airflow first. Make sure there is enough space around the condenser inlet and exhaust as well, a very common problem.

Try Viper Aerosol from Refrigeration Technologies. They list list it as safe for all metals. NSF approved for all food process areas. And the best thing there is no pungent odor like other aerosol sprays from other companies.

Aircraft Mechanical Accessories Technician. The Air Force changed the job title to Air Craft Environmental Systems Technician. But I've decided I'll always be a Mech Acc.

I use NuBrite to clean the Hoshi coils successfully. One trick is to slide the machine back a little so its off the bin and that will help some of the chemical not to go into the bin, but of course a lot will still go into the bin. Remove the condenser fan motor first, its only 4 screws and comes out pretty easy. After you spray it with the Nu-Brite / water mix and it foams up, rinse it out for a loooooong time with water hose, until water goes right through the coil.

On a side note, the self-contained scotsmans can be cleaned the same way, but you can actually unscrew the condenser coil and it will slide out from the back of the ice machine so when you wash it the chemicals just fall onto the floor (for the most part.)

Unfortunatly the coil setup on these make them kinda difficult to get clean once they have been neglected and packed up. The viper product is good as are the ones that stink. I would blow the coil out until nothing comes out anymore before I sprayed anything on it. If there is alot of dirt in it it will turn to mud run to the bottom and stack up and prolong the process. What are your cycle times? Hoshizaki has longer cycles the most other manufacturers. Its a 500 lb machine, if it's on a 1000lb bin and they are using it you may be chasing a problem that's not there. The water and ambient temps could push you freeze time up as long as 50 minuts but 30-35 minuts is pretty common.

Reduced condenser airflow will definitely cause slow ice making. If there are other issues, they will be hard to see without proper airflow as fell. You need to correct the airflow first. Make sure there is enough space around the condenser inlet and exhaust as well, a very common problem.

There is plenty of space by the inlet and exhaust. Definitely nothing restricting the airflow outside of the machine.

Unfortunatly the coil setup on these make them kinda difficult to get clean once they have been neglected and packed up. The viper product is good as are the ones that stink. I would blow the coil out until nothing comes out anymore before I sprayed anything on it. If there is alot of dirt in it it will turn to mud run to the bottom and stack up and prolong the process. What are your cycle times? Hoshizaki has longer cycles the most other manufacturers. Its a 500 lb machine, if it's on a 1000lb bin and they are using it you may be chasing a problem that's not there. The water and ambient temps could push you freeze time up as long as 50 minuts but 30-35 minuts is pretty common.

Thank you so much for your input everybody.

As far as the cycle times go, I know this is a very amateurish question but how do I tell if the machine is in freeze or harvest mode? I do not know how to tell the cycle times.

I will continue to blow out the machine using compressed air, a fine brush and a vacuum until I close the restaurant on Monday when I will be able to use a chemical solution to clean. It will be very difficult for me to use a hose due to the location of the ice machine but if it will be needed to properly clean the coils and fins I will find a way to do so. Thanks again for your help.

As far as the cycle times go, I know this is a very amateurish question but how do I tell if the machine is in freeze or harvest mode? I do not know how to tell the cycle times.

I will continue to blow out the machine using compressed air, a fine brush and a vacuum until I close the restaurant on Monday when I will be able to use a chemical solution to clean. It will be very difficult for me to use a hose due to the location of the ice machine but if it will be needed to properly clean the coils and fins I will find a way to do so. Thanks again for your help.

You can hear the hot gas bypassing during harvest. Go to hoshizaki web sight and down load a pocket manual or order them. Very helpful.

Cycle time is just that. Time from start of freez to start of harvest is your freeze time. Shut machine off for a couple minuts. Turn it back on and listen when it starts. It will be in harvest for I think 90 sec on start up then go into freeze. You will hear the hot gas bypassing, loud hissing, then it will stop when freez cycle starts. Get your times, freez and harvest, then check the chart for that unit. Also will need ambient and water temp. Also if u use chemical and a hose to wash the cond toss all the ice in it or take it out before u start and store in a freezer the clean and sanitize bin when done. Good luck

Cycle time is just that. Time from start of freez to start of harvest is your freeze time. Shut machine off for a couple minuts. Turn it back on and listen when it starts. It will be in harvest for I think 90 sec on start up then go into freeze. You will hear the hot gas bypassing, loud hissing, then it will stop when freez cycle starts. Get your times, freez and harvest, then check the chart for that unit. Also will need ambient and water temp. Also if u use chemical and a hose to wash the cond toss all the ice in it or take it out before u start and store in a freezer the clean and sanitize bin when done. Good luck